Hello, I am a Tcl/Tk core developer. I'm trying to resolve some bugs that have surfaced in Tkinter with Tcl/Tk 8.5. 8.5.0 is very near release, and I'm hoping we can determine where the problem is, and resolve it soon. http://sourceforge.net/tracker/index.php?func=detail&aid=1851526&group_id=12997&atid=112997 It seems very peculiar how the text widget's bbox is returning a Python-like list and therefore breaking the Tcl callback. I haven't thus far been able to determine which python method is causing that, or if it's something related to the hooks you have added. The same problem doesn't occur with 8.4. It also has been suggested by some on the Tcl core team (during discussions about this bug) that you probably shouldn't be using Tcl_GetObjType and relying on the registered Tcl_ObjTypes, however I'm not sure of a way to get what you need otherwise. Tcl 8.5 now supports big integers, so I think some changes may be needed in _tkinter.c for that. The list internal rep has changed as well, and I'm not sure if that will affect you. Another developer also pointed out that the text widget is returning a Tcl_Obj with a list type, rather than a string for the bbox subcommand, so that could be related to this bug. I hope that we can work together to resolve the issues you may have with Tk. George -- http://www.xmission.com/~georgeps/ http://whim.linuxsys.net http://code.google.com/p/megapkg/ http://code.google.com/p/opennexx/